Introduction:

The Mechanical Advantage of a lever is not hard to find. If you can measure the input lever arm and the output lever arm, all you need to do is divide them (input over output). The result is your mechanical advantage, which tells you how much the lever multiplies your strength!

Activity:

• Draw the outline of a tool supplied by your teacher. (Each will be a compound lever.) Label the Fulcrum, Input Lever Arm, and Output Lever Arm.
• Measure the two lever arms, and calculate the Mechanical Advantage.
  • MA=(Input lever Arm)/(Output Lever Arm)
• Line up the tools from lowest to highest mechanical advantage.

Conclusion:

Can you look at a lever and estimate its mechanical advantage?

Practice:

Study the simple machines listed below, and calculate the mechanical advantage of each, choosing the appropriate measurements from all of the data provided on the diagram. (Note: some measurements are irrelevant for calculating MA!)

Enrichment: